alecsandros wrote:What do you mean by "underneath her" ? Torpedoes that come up vertically and hit the ship exactly at her maximum draft ?

The most devastating torpedoes are those designed to pass beneath the target and explode some meters below the keel triggered by the magnetic field. In addition to the shock wave, a giant bubble is created and the great mass of the target ship is no longer supported by sea water. This breaks the back of the target ship. There's really not much in terms of torpedo defense system design that can counter this. I doubt that Vanguard could survive this kind of attack if it was more than one.

The Tirpitz is the only warship that I know of which survived very powerful mines (2,000 kilograms-4,400 lb- of Amtex high explosive) exploding some meters underneath it or almost directly underneath it. Part of this survival was the structural design of the armoured longitudinal bulkheads and the low positioned panzer deck. These structures formed it effect a giant H-beam over the entire length of the citadel that the rest of the ship was constructed around (See MA6).

Dave Saxton wrote:

tommy303 wrote: Large vessels like Vanguard normally had degaussing coils built in to them for protection against such weapons. These reduced the magnetic field around the vessel to below that which would activate the mine or torpedo pistol. Post war, however, magnetic pistols became even more efficient and utilized a system which would sense any change in the magnetic field, allowing even a degaussed vessel to be attacked; this led to a post war mini technology race in improved degaussing vs improved magnetic weapons.

When the British first started testing PPI radars, it was found that de-gaussing could not be used with PPI type CRTs. It would throw the PPI indicators completely out of whack. If the de-gaussing was switched on then it was a long, labor intensive process to restore the radars to functionality. It doesn't appear to have affected magnetrons to as great a degree as CRTs. This may have been why the Germans used electro magnets (adjustable gauss and switchable on/off) for magnetrons and deflection circuits of the Berlin PPI radar systems.

Now that's quite a mouthful. thank you for taking the time to explain it all, dave.

Here is everything I know about war: Someone wins, Someone loses, and nothing is ever the same again. Here is everything I know about life: The only certainties are death and taxes. The enemy of freedom are those who proclaim only they can uphold it.

well personally I think the Vanguard was a bad design. from a battleship vs battleship standpoint, the Vanguard had a serious flaw in the placement and thickness of its armor. since the Vanguard did not carry supercharges, it is clear that to bring an enemy battleship of that era 1935-45 to battle, Vanguards lack of range for her main battery guns, meant that she had to close an enemy in order to engage. the frontal barbette armor was not thick enough to stop enemy shells before she herself would get close enough to open fire. there were many flaws in vanguards design, which included poor structural integrity, inefficient machinery, and no spotting aircraft for long range engagements. they would have been better off

fltcmdr wrote:they would have been better off making Vanguard a 3 turret ship, and taking the guns and turrets from a Nelson class battleship.

Gentlemen,I have often wondered why this was done, after all the RN must have seen what the US had produced with the 'Iowa' class of ship which surely must have outclassed Vanguard in almost every way.I suppose that by the time Vanguard was built the RN must have realised that the battleship era was over and that to redesign the ship to take 3 x 3 gun 16" turrets would take too long which is why they dug out some unwanted WW1 15" from stock.What is a little surprising is that they bothered to actually complete her at all when it was clear that the aircraft carrier was now the queen of the battlefleet.

That used data from books concerning BB vs CV strategies of the various major producers. As late as 1947-1948, if my memory works well, the British and Americans were still undecided on the future direction of production (to build battleships or carriers), because they did not know what the future might bring. The carrier was an excellent asset to attack medium range to long range targets. But the carriers were immensely costly, and took many years to fully work up. They also tended to use planes and pilots, and a huge array of required spare parts and equipment and weapons (both for them and for the planes), which in turn generated massive costs and problems.

The battleship was a classic asset to attack short range targets. They were cheaper to build and operate, were using standardized weapons (the Americans post-war had the 16" and 5" projectiles , along with 40 and 20mm for AA).

they would have been better off making Vanguard a 3 turret ship, and taking the guns and turrets from a Nelson class battleship.

Actually Vanguard was 4 turret version of Lion.

In early 1939 after examination of production capacity it was clear that limiting factor of starting new battleship is production limit of 16” turrets.It was possible to build 7 such a turrets per year. So it was possible to start 2 battleships with 3 turrets per year and 3 battleships every 3 years.After some calculations of possible building new ships in most probable enemies ( that time Germany and Japan ) it was clear that in somewhere around 42-43, Britain will be in short of battleships.Upgrading of industry was considered, and soon approved to increase production capacity to start 3 battleships per year, but it will take time. It was impossible to have extra new battleship in 1943 ( over first 2 Lions ) If she had to be armed by turrets from upgraded industry.But it was possible to build one extra battleship if extra guns and turrets were to be obtained some way.So it was start conception of utilizing existing turrets with 15” guns.Problem was not guns – but turrets. Taking guns from Nelsons changed nothing, as it was need to produce new turrets. Taking whole artillery from Nelsons was not even considered, as those battleships were needed to be on duty, and were not considered to be scrapped.

Expected function of Vanguard was closer to battlecruiser than to battleship. Battlecruiser in more “modern” post Jutland sense of the word. She was considered to be used in far east to fight various cruisers, Kongos, new 12” gunned large japan cruisers ( British believed that they were constructed, we know now that it was myth ) and so one.No classical fight against first class new battleships as a first function, but possible if really needed.She had to “keep the sea” until full scale task force arrives.That was prewar conception.After war started everything was shot down. Than conception was resurrected. For some time it was possible to finish her in 1944, but soon other thing had higher priorities and delays made finishing her in time of was impossible.

Finishing her was good or not? From 20:20 hindsight – clearly wrong. But in time when she was started thing seem to be much differend.And after all – King needed some Yacht